Subaru Forester 2017 Tyre Size: How to Find It, Decode It & Choose Alternatives
If you need a tyre for a 2017 Subaru Forester, the size is written on the car itself — on the door-jamb placard, in the owner's manual, and on the sidewall of the tyre already fitted. This guide walks through all three places in order, explains how to decode the numbers you find there, covers the load index and speed rating that matter just as much as the size, and shows how to judge an alternative size with the ±3% rule. Nothing on this page states a stock size for your exact trim, because that can only be confirmed on your own car.
This is a calculation, not a safety approval. Always check your vehicle's door-jamb placard, load index and speed rating, and confirm fitment with a tyre professional before fitting a different tyre size.
How to find the tyre size on your 2017 Subaru Forester
There are three reliable places to find the size on a 2017 Subaru Forester, and it is worth checking at least two of them so a previous owner's change does not mislead you. The first is the door-jamb placard. Open the driver's door and look at the frame around the opening — on most cars the placard is a sticker there listing the original tyre size for the front and rear, the load index, the speed rating and the recommended cold pressures. On some cars it sits on the passenger door jamb, inside the fuel filler flap, or in the glovebox, so if the driver's jamb is bare, check those spots before giving up. The placard is the manufacturer's statement of what the car was built with, and it is the reference every other check is measured against.
The second place is the owner's manual. The manual lists the approved tyre sizes for your 2017 Subaru Forester, often with a small table by trim or wheel option, and it explains the pressures and the load and speed requirements in words the placard can only hint at. If you bought the car used and the manual is missing, the manufacturer's website usually offers a free download by model year. The third place is the sidewall of the tyre currently on the car. The size is moulded into the rubber in large characters — something like 215/55R17 followed by a load index and speed rating — and reading it takes seconds. But the fitted tyre is only evidence of what is on the car now, not proof of what the car left the factory with. If the sidewall size and the placard disagree, the placard wins, and the difference should be investigated before you order: work out the diameter change with the tyre size calculator and ask a tyre professional whether the fitted size is a suitable alternative.
One more place is worth knowing about for a 2017 Subaru Forester: the VIN plate, usually visible through the windscreen or on a door jamb sticker, identifies the car itself, and a dealer can look up the original specification from the VIN. That is useful when the placard is damaged or unreadable, which happens on older cars. Whatever you find, write the full marking down — size, load index and speed rating together — because the size alone is only part of the order.
subaru forester 2017 tyre size: How to read the tyre size code
A size code is a compact description of the tyre's dimensions. Take 215/55R17 as a worked example for your 2017 Subaru Forester — this is an example code used to show how decoding works, not necessarily the size fitted to your Subaru Forester. The first number, 215, is the section width in millimetres, measured across the widest part of the tyre. The second number, 55, is the aspect ratio: the sidewall height expressed as a percentage of the width, so the sidewall here is 118.2 mm tall. The R stands for radial construction, which is standard on modern cars, and the final number, 17, is the rim diameter in inches — the wheel this tyre fits.
| Measurement | 215/55R17 |
|---|---|
| Section width | 215 mm |
| Aspect ratio | 55% |
| Sidewall height | 118.2 mm |
| Rim diameter | 17 in |
| Overall diameter | 668.3 mm (26.31 in) |
| Circumference | 2099.5 mm |
| Revolutions per mile | 766.5 |
The overall diameter of 668.3 mm is the figure that matters for the speedometer on your 2017 Subaru Forester, and it comes from the rim diameter plus twice the sidewall height. The circumference of 2099.5 mm is the distance the tyre covers in one revolution, and the 766.5 revolutions per mile is the figure gearing calculations use. These are nominal new-tyre dimensions: real tyres vary slightly by brand, model, wear and inflation pressure. After the size code you will see the load index and speed rating, covered next, and sometimes extra markings for reinforced construction or for a tyre designed for a specific purpose. See the full size page for 215/55R17 tyre size for more detail on this example size, or use the tyre size calculator to decode any other size.
subaru forester 2017 tyre size: Load index and speed rating explained
The load index is a number that corresponds to the maximum weight each tyre can carry, and the speed rating is a letter that corresponds to the maximum speed the tyre is designed to sustain. Both appear on the sidewall immediately after the size code, and both must meet or exceed the figures on your 2017 Subaru Forester's placard. A tyre in the right size with a lower load index than the placard asks for is not a like-for-like replacement, however good the price looks. The margin matters most when the car is fully loaded — passengers, luggage and a roof load all count — because the placard figure was set with the car's maximum weight in mind.
The speed rating works the same way on a 2017 Subaru Forester: it must meet the placard minimum. A higher speed rating than required is acceptable, and a lower one is not, even if you never drive at that speed. Winter tyres are the common exception people ask about: they often carry a lower speed rating than summer tyres, and that is only acceptable if the rating still meets the vehicle's minimum requirement. If you are comparing two tyres and one is cheaper, check the full sidewall marking before deciding — the saving is often in the rating, not in the size. The tyre load index calculator explains the load index scale, and the tyre speed rating calculator covers the speed rating letters.
Tyre age, damage and when to replace for subaru forester 2017 tyre size
Tyres age even when they are not worn out, and on a 2017 Subaru Forester that covers low annual mileage this matters as much as tread depth. The sidewall carries a four-digit date code — the week and year of manufacture — so you can see how old each tyre actually is. Rubber hardens and cracks with age, sunlight and ozone, and a tyre that still has tread can still be past its best after several years, particularly if the car stands outside. Check the sidewalls and the tread grooves for fine cracks, bulges or cuts, and check the spare too: a spare that has never been used is still ageing. Replace any tyre with a bulge, a deep cut, or visible cord, and have any tyre that has hit a pothole or kerb hard inspected even if it still holds air, because internal damage does not always show on the outside. There is no single universal age limit — guidance differs by maker and by country — so use the date code, the visible condition and a professional inspection together, and do not judge a tyre by tread depth alone.
subaru forester 2017 tyre size: Choosing an alternative size: the ±3% rule
If you are thinking of a different size from the one on the placard on your 2017 Subaru Forester — a slightly wider tyre, a taller sidewall, or a plus-size wheel change — the commonly used guideline is to stay within ±3% of the original diameter. That keeps the speedometer error small and the gearing close to how the car was designed. It is a guideline, not a safety approval: it says nothing about whether the tyre clears the arches, suits the wheel width, or carries the load your vehicle needs. To use it, take your placard diameter and work out the range. Using the example size 215/55R17 (668.3 mm) as the arithmetic example, ±3% gives a range from 648.3 mm to 688.3 mm — any alternative whose diameter falls inside that range keeps the speedometer within 3%. The same maths works for your real size: look up both diameters in the chart or with the tyre size comparison tool, divide the new diameter by the old one, subtract 1 and multiply by 100 to get the percentage change.
Remember that a different size on your 2017 Subaru Forester also changes the sidewall height, and with it the ride: a taller sidewall generally absorbs bumps a little better, while a shorter sidewall sharpens the steering feel. A wider tyre changes the contact patch and needs a wheel wide enough to support it. And the pressures change too — the placard pressure was set for the original size, so a different size may need a different pressure. Work the numbers first, then confirm the physical fit on the car and with a tyre professional. The speedometer error calculator shows the exact speedometer effect at 30, 50 and 70 mph for any pair of sizes.
Common mistakes to avoid for subaru forester 2017 tyre size
- Forgetting the spare on your 2017 Subaru Forester: a changed road-tyre size leaves the spare mismatched, and a temporary spare has speed and distance limits.
- Judging a tyre on your 2017 Subaru Forester by tread depth only and ignoring age, cracking and the date code on the sidewall.
- Assuming a size fits your 2017 Subaru Forester because the diameter is within ±3% — that rule is about the speedometer, not about physical clearance.
- Ordering by model and year alone for a 2017 Subaru Forester, without checking the placard — the same model year can wear different sizes across trims.
- Copying the size from a tyre that a previous owner fitted to a 2017 Subaru Forester, which may itself be an alternative rather than the original size.
A final point for your 2017 Subaru Forester: buy tyres in axle pairs at least, and ideally as a matching set of four. Different tread patterns, compounds and wear levels across an axle change how the car behaves in the wet and under braking, and mixing a new tyre with a worn one on the same axle is a false economy. Keep the receipt and the size details, and check the pressures again a week after fitting, since new tyres can settle slightly.
Related pages for subaru forester 2017 tyre size
Browse the vehicles hub or compare nearby model years: Subaru Forester 2016 tyre size, Subaru Forester 2018 tyre size, Subaru Forester 2015 tyre size. You can also check the tyre size calculator and the tyre pressure calculator before you order.
Frequently asked questions
How often should I replace the tyres on my 2017 Subaru Forester?
Replace them when the tread reaches the legal minimum in your jurisdiction, when you see cracks, bulges or damage, or when the tyre is old enough that the rubber has hardened — check the four-digit date code on the sidewall. Tread depth alone does not tell the whole story. Write the full marking down for your 2017 Subaru Forester and order against that, not against a generic table.
What tyre size does a 2017 Subaru Forester take?
There is no single answer for every 2017 Subaru Forester, because the size varies by trim and optional wheels. The correct size for your car is on the door-jamb placard, in the owner's manual, and on the sidewall of the tyre currently fitted. Read it there rather than ordering from a generic table. For your 2017 Subaru Forester, the placard and the owner's manual are the final word on this.
Where is the tyre size placard on a 2017 Subaru Forester?
On most cars it is on the driver's door jamb — the frame you see when the driver's door is open — sometimes on the inside of the fuel filler flap or in the glovebox. It lists the original tyre size, the load index, the speed rating and the cold tyre pressures. That is the check to run on your own 2017 Subaru Forester before ordering anything.
Can I fit a different tyre size on my 2017 Subaru Forester?
You can consider an alternative within ±3% of the original diameter as a starting point, but that is only a guideline for the speedometer. Clearance, wheel width, load index and speed rating all have to be checked on your car and confirmed with a tyre professional before fitting. Keep the placard figure for your 2017 Subaru Forester beside you when you compare tyres.
What happens if the placard and the fitted tyre disagree for subaru forester 2017 tyre size?
Trust the placard for what the car was built with, and treat the fitted tyre as a clue that a previous owner may have changed the size. If they disagree, work out the diameter difference with the tyre size calculator and ask a tyre professional whether the fitted size is a suitable alternative for your car. If in doubt about your 2017 Subaru Forester, a tyre professional can confirm it from the placard in seconds.